Fabrication of a Simple Cast-deposited Nafion/multi-walled Carbon Nanotube Composite Film as a Sensor for Voltammetric Determination of Pethidine

The effect of surface modification of glassy carbon electrode (GCE) by multi-walled carbon nanotubes (MWNTs) and Nafion (Nafion/MWCNT/MGCE) has been studied to voltammetric determination pethidine (PTD) as a potent opiate analgesic for humans for the first time. Cyclic Voltammetry (CV) and scanning electron microscopy (SEM) were used to characterize the properties of the modified electrode. The Nafion/MWCNT/MGCE exhibited a well-defined anodic peak at pH 7.0 at a potential of ~ 0.85 V for the oxidation of PTD as compared to 1.2 V at GCE. Using differential pulse voltammetry (DPV) technique a linear calibration curve was obtained over PTD concentration range 1.0-80.0 ?M in phosphate buffer solution of pH 7.0 with detection limit of 0.83 ?M. The method has been found selective and successfully implemented for the determination of PTD in human urine and injection samples using standard addition method. The electrode exhibited an efficient catalytic response with good reproducibility and stability